Notes: Data used for passenger travel are from the preliminary National Household Travel Survey (NHTS) travel-day file and include trips of all lengths made by respondents on a single day; about 95 percent of these daily trips were 30 miles or less. Calculations are based on preliminary weighted estimates from the 2001 NHTS.

Sources: Passenger-USDOT, Federal Highway Administration and Bureau of Transportation Statistics, National Household Travel Survey database, available at http://nhts.ornl.gov, as of January 2003. Freight-USDOT, Bureau of Transportation Statistics, and U.S. Department of Commerce, U.S. Census Bureau, 1997 Commodity Flow Survey (Washington, DC: 1999); plus additional estimates prepared by BTS, October 2002.